package com.linlang.grasharepro.utils;

/**
 * Created by lixin on 2016-8-7.
 */

import android.view.View;
import android.view.ViewGroup;
import android.widget.ListAdapter;
import android.widget.ListView;

/**
 * ListView 常用工具方法
 * 用于解决一些疑难杂症问题
 * Created by pengtao on 2016/6/3.
 */
public class ListViewUitls {

    /**
     * 为了解决ListView在ScrollView中只能显示一行数据的问题
     * @param listView
     */
    public static void setListViewHeightBasedOnChildren(ListView listView) {
        // 获取ListView对应的Adapter
        ListAdapter listAdapter = listView.getAdapter();
        if (listAdapter == null) {
            return;
        }

        int totalHeight = 0;
        for (int i = 0, len = listAdapter.getCount(); i < len; i++) { // listAdapter.getCount()返回数据项的数目
            View listItem = listAdapter.getView(i, null, listView);
            listItem.measure(0, 0); // 计算子项View 的宽高
            totalHeight += listItem.getMeasuredHeight(); // 统计所有子项的总高度
        }

        ViewGroup.LayoutParams params = listView.getLayoutParams();
        params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
        // listView.getDividerHeight()获取子项间分隔符占用的高度
        // params.height最后得到整个ListView完整显示需要的高度
        listView.setLayoutParams(params);
    }
}